Montgomery County Fire and Rescue Services has evacuated a building of the National Military Medical Center’s Carderock Clinic at 9500 MacArthur Boulevard after a chemical spill, according to Fire spokeswoman Beth Anne Nesselt.

Building 60, which holds a Navy Medical cardiac unit, was evacuated around 11:30 a.m. after an unknown chemical was spilled in the loading dock area, Nesselt said.

MCFRS is currently isolating the area and shutting down HVAC units inside the building.

Nesselt said Hazmat units will arrive at the scene to determine what type of chemical spilled, how much of it spilled and what steps to take next.